Roll holder unit for printer

ABSTRACT

A roll holder unit for a printer includes a regulating wall, a movable arm, and a lock arm. The regulating wall is located on the same axial side of the roll as the regulating wall to prevent axial movement of a roll. The movable arm moves between an adjacent position in which the axle is contact with a shaft and a spaced-apart position in which the axle is apart from the shaft. The movable arm is biased toward the adjacent position from the spaced-apart position. The lock arm moves between a regulating position in which the lock arm regulates the movable arm from moving from the adjacent position to the spaced-apart position and a release position in which the lock arm allows the movable arm to move from the adjacent position to the spaced-apart position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2010-049381, filed on Mar. 5, 2010, the entire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to a roll holder unit for a printer.

BACKGROUND

In the related art, there is known a roll holder unit that holds a printer paper roll by applying a biasing force to the side surface of the paper roll with a biasing member provided in one axial end portion of the paper roll.

However, the related roll holder unit suffers from a problem in that the paper roll is likely to move because the roll holder unit does not have any paper roll locking portion but merely holds the paper roll with a biasing force applied to the side surface of the paper roll by a biasing member.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a printer having a roll holder unit for a printer with a cover kept in an open state.

FIG. 2 is a perspective view showing a roll holding mechanism provided within the roll holder unit for a printer.

FIG. 3 is a front view showing a roll, a regulating wall and a movable arm when the roll is moved toward a set position.

FIG. 4 is a front view showing the regulating wall, the movable arm and a lock arm when the roll is set in the set position.

FIG. 5 is a side view of the printer having the roll holder unit for a printer with the cover kept in an open state.

FIG. 6 is a side view of the printer having the roll holder unit for a printer with the cover kept in a closed state.

DETAILED DESCRIPTION

According to one embodiment, a roll holder unit for a printer includes a regulating wall, a movable arm, and a lock arm. The regulating wall is located on the same axial side of the roll as the regulating wall to prevent axial movement of a roll. The movable arm moves between an adjacent position in which the axle is contact with a shaft of the roll and a spaced-apart position in which the axle is apart from the shaft. The movable arm is biased toward the adjacent position from the spaced-apart position. The lock arm moves between a regulating position in which the lock arm regulates the movable arm from moving from the adjacent position to the spaced-apart position and a release position in which the lock arm allows the movable arm to move from the adjacent position to the spaced-apart position.

One embodiment of a roll holder unit for a printer will now be described in detail with reference to the accompanying drawings.

The roll holder unit for printer 1 (hereinafter simply referred to as “unit 1”) is mounted to a printer. The unit 1 is designed to removably and rotatably hold a roll 3 of strip-shaped continuous paper 2. The printer prints on the continuous paper 2 drawn from the roll 3 of the unit 1.

The unit 1 includes a housing 4 divided into a base 4A having a depressed portion 4 a for accommodating components and a cover 4B having a depressed portion 4 b for covering the components. The base 4A and the cover 4B are coupled to each other by a hinge mechanism (not shown) for rotation about a hinge axis Ah. The cover 4B openably covers the base 4A.

A plurality of ribs 4 c (five ribs 4 c in the present embodiment) each having an arc-shaped cutout and being perpendicular to the hinge axis Ah protrudes from the inner surface of the cover 4B in a mutually parallel spaced-apart relationship. The opposite end portions of the ribs 4 c from the hinge axis Ah are connected to a transverse wall 4 d parallel to the hinge axis Ah. In the present embodiment, the ribs 4 c and the transverse wall 4 d serve to enhance the rigidity of the cover 4B. When the cover 413 is in a closed state, the arc-shaped cutouts of the ribs 4 c serve to create a clearance between the ribs 4 c and the roll 3 set in the base 4A and between the ribs 4 c and regulating walls 6 (see FIG. 6). In addition, a thermal head 10 is provided in the cover 4B.

A roll holding mechanism 9 including a base portion 5, a pair of regulating walls 6, a pair of movable arms 7 and a pair of lock arms 8 is installed on the base 4A. As shown in FIG. 1, the regulating walls 6 protrude from the base portion 5 in a mutually parallel spaced-apart relationship. The roll holding mechanism 9 holds the roll 3 by interposing the roll 3 between the regulating walls 6 so that they are closely spaced apart to be in contact. An operator (user) raises the lock arms 8 up into the release position Pa2 shown in FIG. 1 and then sets the roll 3 in the set position Ps by bringing the roll 3 toward the roll holding mechanism 9 from above. Subsequently, the operator (user) turns the lock arms 8 clockwise in FIG. 1 about a rotational axis Ai to bring the lock arms 8 into the regulating position Pa1 (see FIG. 6), thereby locking the roll 3 in the set position Ps. The roll holding mechanism 9 is configured to be symmetrical along an imaginary plane perpendicular to the axis C of the roll 3. A platen roller 11 facing the thermal head 10 is provided in the base 4A. A paper is brought between the platen roller 11 and the thermal head, and the platen roller 11 is rotatably driven by a motor (not shown). In this manner the paper 12 is drawn from the roll 3.

As shown in FIG. 2, the base portion 5 includes a rectangular bottom wall section 5 a and a side wall section 5 b surrounding the periphery of the bottom wall section 5 a. Each of the regulating walls 6 includes a rectangular base section 6 a placed on the bottom wall section 5 a and a transverse wall section 6 b vertically protruding from the base section 6 a. A circular through-hole 6 c is provided in the transverse wall section 6 b. The width of the peripheral edge portion of the through-hole 6 c is substantially uniform. The upper portion of the transverse wall section 6 b has a ring shape.

Each of the movable arms 7 includes a leaf spring 7 a as an arm portion and an axle 7 b fixed to the tip end of the leaf spring 7 a and movable in response to the elastic deformation of the leaf spring 7 a. The leaf spring 7 a is contiguous to the outer surface 6 d of each of the regulating walls 6. The base end section, i.e., lower section, of the leaf spring 7 a is fixed to the base section 6 a of each of the regulating walls 6. The leaf spring 7 a extends upwards from the bottom wall section 5 a along the outer surface 6 d of the regulating wall 6 in the form of a strip with a specified width. The upper end section of the leaf spring 7 a acts as a free end. In this regard, the movement of the leaf spring 7 a toward the roll 3 is regulated by each of the regulating walls 6. In contrast, the movement of the leaf spring 7 a away from the roll 3 is not regulated if each of the lock arms 8 is in an upright state. Therefore, as shown in FIG. 1, the leaf spring 7 a can be elastically bent away from the axis of the roll 3. In the present embodiment, the leaf spring 7 a corresponds to an elastic member.

The axle 7 b includes a cylindrical columnar protrusion 7 c protruding away from the roll 3. The protrusion 7 c is press-fitted to the circular through-hole 7 d formed in the leaf spring 7 a and protrudes away from the roll 3 through the through-hole 7 d. In the present embodiment, the leaf spring 7 a fixedly holds the axle 7 b. However, this is presented only by way of example. The leaf spring 7 a may hold the axle 7 b in such a manner that the axle 7 b can rotate about the through-hole 7 d as a bearing.

The axle 7 b includes a frusto-conical insertion section 7 e protruding toward the roll 3 and inserted into the shaft 3 a of the roll 3 (see FIGS. 3 and 4). As shown in FIG. 4, when the leaf spring 7 a is raised up into the adjacent position Pb1, the axle 7 b extends through the through-hole 6 c of each of the regulating walls 6 and the insertion section 7 e is inserted into the opening 3 b of the shaft 3 a of the roll 3. The tip end side of the insertion section 7 e is chamfered to form a slant surface 7 f.

As shown in FIG. 2, the axle 7 b includes three extension sections 7 g extending radially outwards of the roll 3 between the leaf spring 7 a and the insertion section 7 e. If the gap between the inner surfaces 6 e and 6 e of the mutually opposing transverse wall sections 6 b becomes the same as the width W of the roll 3 (see FIG. 1), the surfaces 7 h of the extension sections 7 g facing toward the roll 3 will make contact with the axial end portion 3 c of the roll 3 as shown in FIG. 4.

In addition, as shown in FIG. 2, rails 5 c extending along the axial direction of the roll 3 are provided on the bottom wall section 5 a of the base portion 5. The regulating walls 6 may slide along the longitudinal direction of the rails 5 c, i.e., the axial direction of the roll 3.

When setting the roll 3 in the roll holding mechanism 9, an operator (user) first causes the regulating walls 6 to slide along the rails 5 c, thereby positioning a pair of the regulating walls 6 in such a state that the gap between the inner surfaces 6 e and 6 e of the mutually opposing transverse wall sections 6 b becomes substantially equal to the width W of the roll 3.

Then, as shown in FIG. 1, the operator (user) brings the roll 3 toward the roll holding mechanism 9 from above. At this time, as illustrated in FIG. 3, the axial end portion 3 c of the roll 3 presses the axle 7 b axially outwards. Thus, the movable arm 7 may be elastically bent to lean away from the roll 3. The position of the movable arm 7 available at this time corresponds to a spaced-apart position Pb2. When the roll 3 initially makes contact with the axle 7 b, the lower end of the axial end portion 3 c of the roll 3 comes into contact with the slant surface 7 f of the axle 7 b. Therefore, as compared with the case where the slant surface 7 f is not formed in the axle 7 b, the roll 3 can smoothly move downwards and the movable arm 7 can lean more smoothly.

If the operator (user) further moves the roll 3 downwards, as illustrated in FIG. 4, the movable arm 7 is returned from a leaning orientation to an upright orientation by the elastic biasing force of the leaf spring 7 a. Consequently, the insertion section 7 e of the axle 7 b is inserted into the shaft 3 a. This establishes a state where the roll holding mechanism 9 holds the roll 3 tight. The position of the movable arm 7 at this time corresponds to an adjacent position PM. Although the configuration and operation of only one axial end portion is shown in FIGS. 3 and 4, this configuration and operation works in the other axial end portion in the same manner (which has a mirror image relationship with the one axial end portion). According to the present embodiment, the operator (user) can attach the roll 3 to the roll holding mechanism 9 in an easy manner by bringing the roll 3 toward the roll holding mechanism 9 (moving the roll 3 downwards in the present embodiment). When removing the roll 3 from the roll holding mechanism 9, the operator (user) can easily take out the roll 3 by raising the lock arms 8 from the regulating position Pa1 to the release position Pa2 and then pulling the roll 3 upwards from the roll holding mechanism 9.

The lock arms 8 are rotatably supported on the outer surfaces 6 d of the regulating walls 6 for rotation about the rotational axis A1 parallel to the axis C of the roll 3. Each of the lock arms 8 can be shifted by the operator (user) between the upright release position Pa2 (see FIGS. 1 and 5) and the leaning regulating position Pa1 (see FIGS. 4 and 6).

As shown in FIG. 4, in the regulating position Pa1, each of the lock arms 8 is positioned on the opposite side of the roll 3 with respect to the leaf spring 7 a of each of the movable arms 7. Accordingly, in this state, the leaf spring 7 a is interposed between each of the regulating walls 6 and each of the lock arms 8. In the regulating position Pa1, the lock arms 8 regulate the movable arms 7 from leaning.

As illustrated in FIG. 5, in the release position Pa2, each of the lock arms 8 protrudes relatively high from the base 4A. The direction in which each of the lock arms 8 rotates about the rotational axis Ai from the release position Pa2 to the regulating position Pa1 (namely, the clockwise direction in FIGS. 5 and 6) coincides with the direction in which the cover 4B rotates about the axis Ah from the open state to the closed state (namely, the clockwise direction in FIGS. 5 and 6). Therefore, in the present embodiment, if the operator (user) closes the cover 4B, the cover 4B pushes and brings down the lock arms 8 staying in the release position Pa2, thereby inclining the lock arms 8 toward the regulating position Pa1. This makes it possible to reliably move the lock arms 8 into the regulating position Pa1.

In the present embodiment, the movable arms 7 and the lock arms 8 are fixed to the regulating walls 6. Therefore, when the regulating walls 6 are caused to slide along the rails 5 c installed on the base portion 5, the movable arms 7 and the lock arms 8 can also move along with the regulating walls 6. This makes it possible to reliably obtain the effects provided by the movable arms 7 and the lock arms 8, regardless of the position of the regulating walls 6, i.e., the width W of the roll 3.

In the present embodiment, the transverse wall 4 d of the cover 4B regulates the movement of the lock arms 8 from the regulating position Pa1 to the release position Pa2. That is, if the cover 4B is closed as shown in FIG. 6, the transverse wall 4 d are located close to or on contact with the tip end portions of the lock arms 8. In the present embodiment, the transverse wall 4 d corresponds to an unlock regulating portion. In this regard, as shown in FIG. 1, the transverse wall 4 d extends parallel to the hinge axis Ah. Thus, the transverse wall 4 d can regulate the movement of the lock arms 8 regardless of the position of the regulating walls 6 depending on the size of the roll 3.

In the present embodiment, the axle 7 b regulates the movement of the lock arms 8 toward the opposite side of the regulating position Pa1 from the release position Pa2. As shown in FIG. 6, when in the regulating position Pa1, each of the lock arms 8 is arranged on the protrusion 7 c of the axle 7 b and extends in the direction crossing the leaf spring 7 a. In the present embodiment, the protrusion 7 c regulates each of the lock arms 8 from rotating downwards, which assists in maintaining the state in which each of the lock arms 8 lies on the opposite side of the leaf spring 7 a from the roll 3 and regulates the leaf spring 7 a from leaning. This makes it possible reduce the amount of labor used during the manufacturing process and to reduce production cost, as compared with the case where a member for regulating the movement of the lock arms 8 toward the opposite side of the regulating position Pa1 from the release position Pa2 is provided separately with the axle 7 b.

As described above, the roll holder unit 1 for a printer according to the present embodiment includes the regulating walls 6, the movable arms 7 and the lock arms 8. Each of the regulating walls 6 is provided on at least one axial side of the roll 3 (on both sides of the roll 3 in the present embodiment) opposite the axial end portion 3 c of roll 3, thereby regulating the axial movement of the roll 3. Each of the movable arms 7 is provided on the same side as each of the regulating walls 6 from the roll 3 and can move between the adjacent position Pb1 in which the axle 7 b positioned close to the axial end portion 3 c of the roll 3 comes into the shaft 3 a and a spaced-apart position Pb2 in which the axle 7 b positioned distant from the axial end portion 3 c of the roll 3 moves away from the shaft 3 a. The movable arms 7 are elastically biased from the spaced-apart position Pb2 toward the adjacent position Pb1. Further, the lock arms 8 are provided to move between the regulating position Pa1 in which the lock arms 8 regulate the movable arms 7 from moving from the adjacent position Pb1 to the spaced-apart position Pb2 and the release position Pa2 in which the lock arms 8 allow the movable arms 7 to move from the adjacent position Pb1 to the spaced-apart position Pb2. According to the present embodiment, therefore, the roll 3 can be easily mounted and removed using the movable arms 7 while reliably regulating the movement of the roll 3 with the regulating walls 6. When the movable arms 7 are kept in the adjacent position Pb1, the axle 7 b comes into the shaft 3 a, which makes it possible to reliably hold the roll 3 tight. According to the present embodiment, it is possible to attach and remove the roll 3 with ease and to reliably hold the roll 3 tight.

In the present embodiment, each of the movable arms 7 includes the leaf spring 7 a as a elastic member supporting the axle 7 b and biasing the axle 7 b in the direction in which the insertion section 7 e of the axle 7 b is inserted into the shaft 3 a. Consequently, it is possible to simplify the configuration and to reduce the production cost, as compared with the case where a member for supporting the axle 7 b and a biasing member are provided separately.

In the present embodiment, the leaf spring 7 a supports the axle 7 b in a state that the axle 7 b passes through the through-hole 7 d along the axial direction of the roll 3. The lock arms 8 are provided to rotate about the rotational axis Ai parallel to the axis C of the roll 3. The movement of the lock arms 8 toward the opposite side of the regulating position Pa1 from the release position Pa2 is regulated by the axle 7 b. Use of the axle 7 b makes it possible to provide a relatively simple configuration for regulating the movement of the lock arms 8 toward the opposite side of the regulating position Pa1 from the release position Pa2.

In the present embodiment, the cover 4B includes the transverse wall 4 d as an unlock regulating portion to regulate the movement of the lock arms 8 from the regulating position Pa1 toward the release position Pa2 when the cover 4B is kept in a closed state. Accordingly, if an operator (user) closes the cover 4B, the movement of the lock arm 8 can be easily regulated.

In the present embodiment, each of the movable arms 7 is arranged on the opposite side of each of the regulating walls 6 from the roll 3 and is provided with the through-hole 6 c as a penetration portion through which the axle 7 b passes. Therefore, the axial movement of the roll 3 can be reliably regulated by bringing the relatively wide area around the through-hole 6 c into an opposing relationship with the axial end portion 3 c of the roll 3.

In the present embodiment, the lock arms 8 are movably supported on the regulating walls 6. Therefore, the effects provided by the lock arms 8 can be obtained regardless of the position of the regulating walls 6. In the present embodiment, the movable arms 7 are also movably supported on the regulating walls 6. As a result, the effects provided by the movable arms 7 can be obtained regardless of the position of the regulating walls 6.

While certain embodiments have been described above, these embodiment have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the embodiments described herein may be embodied in a variety of other forms. For example, the specifications (shape, structure, number, material, arrangement, etc.) of the regulating walls, the movable arms, the lock arms, the leaf spring, the axle, the base, the cover, the unlocking and regulating portion and the penetration portion may be embodied in other suitable forms. The present embodiments may be applied to other rolls other than paper rolls. The lock arms may be connected to each other to operate as a unit. It may be possible to use other elastic members other than a leaf spring. Various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions. 

1. A roll holder unit for a printer, comprising: a regulating wall that regulates axial movement of a roll located on at least one axial side of the roll in opposing relationship with one axial end portion of the roll; a movable arm comprising an axle that supports the roll, the movable arm located on the same axial side of the roll as the regulating wall and configured to move between an adjacent position in which the axle is in contact with a shaft of the roll and a spaced-apart position in which the axle is apart from the shaft, the movable arm biased toward the adjacent position from the spaced-apart position; and a lock arm configured to move between a regulating position in which the lock arm regulates the movable arm from moving from the adjacent position to the spaced-apart position and a release position in which the lock arm allows the movable arm to move from the adjacent position to the spaced-apart position.
 2. The roll holder unit of claim 1, wherein the movable arm comprises an elastic member supporting the axle and biasing the axle in a direction in which the axle is in contact with the shaft.
 3. The roll holder unit of claim 2, wherein the elastic member supports the axle in a state that the axle penetrates the roll in an axial direction, the lock arm is rotatable about a rotational axis extending parallel to an axis of the roll, and the axle regulate the lock arm from moving toward the opposite side of the regulating position from the release position.
 4. The roll holder unit of claim 1, further comprising: a base supporting the regulating wall, the movable arm, and the lock arm; and a cover to openably cover the base, wherein the cover comprises an unlock regulating portion to regulate the lock arm from moving from the regulating position toward the release position when the cover is closed.
 5. The roll holder unit of claim 1, wherein the movable arm is arranged on the opposite side of the regulating wall from the roll, and the regulating wall comprises a penetration portion through which the axle passes.
 6. The roll holder unit of claim 1, wherein the lock arm is movably supported on the regulating wall.
 7. The roll holder unit of claim 1 wherein the regulating wall is located on both axial sides of the roll.
 8. A roll holder comprising: a regulating wall located on at least one axial side of a roll; a movable arm located on the same axial side of the roll as the regulating wall, the movable arm comprising an axle movable between an adjacent position in which the axle engages the roll and a spaced-apart position in which the axle disengages the roll; and a lock arm that moves between a regulating position that prevents the movable arm from moving from the adjacent position to the spaced-apart position, and a release position in which the lock arm allows the movable arm to move from the adjacent position to the spaced-apart position.
 9. The holder of claim 8, wherein the movable arm further comprises an elastic member supporting the axle which biases the axle in a direction in which the axle is inserted into a shaft of the roll.
 10. The holder of claim 9, wherein the elastic member supports the axle so that the axle penetrates the roll in an axial direction, the lock arm is rotatable about a rotational axis extending parallel to an axis of the roll, and the axle regulates the lock arm from moving toward the opposite side of the regulating position from the release position.
 11. The holder of claim 8, further comprising: a base supporting the regulating wall, the movable arm, and the lock arm; and a cover to openably cover the base, the cover comprising an unlock regulating portion to regulate the lock arm from moving from the regulating position toward the release position when the cover is closed.
 12. The holder of claim 8, wherein the movable arm is located on the opposite side of the regulating wall from the roll, and the regulating wall comprises a penetration portion through which the axle passes.
 13. The holder of claim 8, wherein the lock arm is movably supported on the regulating wall.
 14. The holder of claim 8, wherein the regulating wall is located on both axial sides of the roll.
 15. A method for securing a roll in a roll holder, the method comprising: restricting axial movement of the roll with a regulating wall located on at least one axial side of the roll; engaging the roll with a movable arm located on the same axial side of the roll as the regulating wall, the movable arm comprising an axle movable between an adjacent position in which the axle engages the roll and a spaced-apart position in which the axle disengages the roll; and locking the roll into position with a lock arm that moves between a regulating position that prevents the movable arm from moving from the adjacent position to the spaced-apart position, and a release position in which the lock arm allows the movable arm to move from the adjacent position to the spaced-apart position.
 16. The method of claim 15, further comprising biasing the axle into a shaft of the roll with an elastic member of the movable arm that supports the axle.
 17. The method of claim 15, wherein the elastic member supports the axle so that the axle penetrates the roll in an axial direction, the lock arm is rotatable about a rotational axis extending parallel to an axis of the roll, and the axle regulates the lock arm from moving toward the opposite side of the regulating position from the release position.
 18. The method of claim 15, further comprising: supporting the regulating wall, the movable arm, and the lock arm with a base; and openably covering the base with a cover comprising an unlock regulating portion to regulate the lock arm from moving from the regulating position toward the release position when the cover is closed.
 19. The method of claim 15, wherein the movable arm is located on the opposite side of the regulating wall from the roll, and the regulating wall comprises a penetration portion through which the axle passes.
 20. The method of claim 15, further comprising movably supporting the lock arm on the regulating wall. 